GMaps.prototype.checkGeofence = function (lat, lng, fence) {
    return fence.containsLatLng(new google.maps.LatLng(lat, lng));
};

GMaps.prototype.checkMarkerGeofence = function (marker, outside_callback) {
    if (marker.fences) {
        for (var i = 0, fence; fence = marker.fences[i]; i++) {
            var pos = marker.getPosition();
            if (!this.checkGeofence(pos.lat(), pos.lng(), fence)) {
                outside_callback(marker, fence);
            }
        }
    }
};
